MariaDB [fechas]> create table estudiante (
    -> carnet varchar (3) primary key,
    -> nombre varchar(50),
    -> fechamatricula date,
    -> fechanacimiento date,
    -> sexo char (1)
    -> );
Query OK, 0 rows affected (0.023 sec)

MariaDB [fechas]> cretae table materia (
    -> codigom varchar (3) primary key,
    -> descripcion varchar (50),
    -> valor int
    -> );
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'cretae table materia (
codigom varchar (3) primary key,
descripcion varchar (...' at line 1
MariaDB [fechas]> create table materia (
    -> codigom varchar(3) primary key,
    -> descripcion varchar(50),
    -> valor int
    -> );
Query OK, 0 rows affected (0.022 sec)

MariaDB [fechas]> create table estmat (
    -> carnet varchar (3),
    -> codigom varchar (3),
    -> foreign key (carnet) references estudiante(carnet),
    -> foreign key (codigom) references materia(codigom)
    -> );
Query OK, 0 rows affected (0.048 sec)

MariaDB [fechas]> insert into estudiante values
    -> ('001','maria', '2010-01-15', '1966-05-13', 'f'),
    -> ('002','juana', '2010-06-08', '1973-01-22', 'f'),
    -> ('003','carlos', '2010-06-28', '1976-03-05', 'm'),
    -> ('004','maria parra', '2010-06-11', '1976-08-15', 'f'),
    -> ('005','pablo neruda', '2011-02-13', '1990-08-25', 'm'),
    -> ('006','bladimir palacio', '2011-02-04', '1994-09-03', 'm'),
    -> ('007','apolonia serrano', '2011-02-28', '1994-03-09', 'f'),
    -> ('008','federico serrano', '2011-03-05', '1991-06-10', 'm');
Query OK, 8 rows affected (0.082 sec)
Records: 8  Duplicates: 0  Warnings: 0

MariaDB [fechas]> insert into materia values
    -> ('001', 'software I', 320000),
    -> ('002', 'software II', 328000),
    -> ('003', 'software III', 400000),
    -> ('004', 'matematicas', 300000),
    -> ('005', 'ingles', 300000);
Query OK, 5 rows affected (0.015 sec)
Records: 5  Duplicates: 0  Warnings: 0

MariaDB [fechas]> insert into estmat values
    -> ('001', '003'), ('001', '005'), ('002', '002'), ('002', 003'), ('002', '004'),
    '> ('003', '004'), ('003', '001'), ('004', '004'), ('004', '005'), ('005', '002'), 
    '> ('005', '005'), ('006', '001'), ('006', '005'), ('007', '003'), ('007', '004'),
    '> ('008', '001'), ('008', '004'), ('008', '005');
    '> ;
    '> ';
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ''), ('002', '004'),
('003', '004'), ('003', '001'), ('004', '004'), ('004', '...' at line 2
MariaDB [fechas]> insert into estmat values
    -> ('001', '003'), ('001', '005'), ('002', '002'), ('002', '003'), ('002', '004'),
    -> ('003', '004'), ('003', '001'), ('004', '004'), ('004', '005'), ('005', '002'),
    -> ('005', '005'), ('006', '001'), ('006', '005'), ('007', '003'), ('007', '004'),
    -> ('008', '001'), ('008', '004'), ('008', '005');
Query OK, 18 rows affected (0.016 sec)
Records: 18  Duplicates: 0  Warnings: 0

MariaDB [fechas]> select count(*) as total from estudiante where year(fechanacimiento) between 1970 and 1979;
+-------+
| total |
+-------+
|     3 |
+-------+
1 row in set (0.002 sec)

MariaDB [fechas]> select * from estudiante where timestampdiff(year, fechanacimiento, curdate()) between 16 and 20;
Empty set (0.001 sec)

MariaDB [fechas]> SELECT * FROM estudiante WHERE TIMESTAMPDIFF(YEAR, fechanacimiento, CURDATE()) BETWEEN 16 AND 20;
Empty set (0.001 sec)

MariaDB [fechas]> select nombre from estudiante where timestampdiff(year, fechanacimiento,curdate()) > 25;
+------------------+
| nombre           |
+------------------+
| maria            |
| juana            |
| carlos           |
| maria parra      |
| pablo neruda     |
| bladimir palacio |
| apolonia serrano |
| federico serrano |
+------------------+
8 rows in set (0.001 sec)

MariaDB [fechas]> select nombre, timestampdiff(year, fechanacimiento, curdate()) as edad from estudiante;
+------------------+------+
| nombre           | edad |
+------------------+------+
| maria            |   58 |
| juana            |   52 |
| carlos           |   49 |
| maria parra      |   48 |
| pablo neruda     |   34 |
| bladimir palacio |   30 |
| apolonia serrano |   31 |
| federico serrano |   33 |
+------------------+------+
8 rows in set (0.001 sec)

MariaDB [fechas]> select descripcion, if(valor > 300000, 'cara', 'econĒmica') as precio from materia;
+--------------+-----------+
| descripcion  | precio    |
+--------------+-----------+
| software I   | cara      |
| software II  | cara      |
| software III | cara      |
| matematicas  | econĒmica |
| ingles       | econĒmica |
+--------------+-----------+
5 rows in set (0.001 sec)

MariaDB [fechas]> alter table estudiante add edad int;
Query OK, 0 rows affected (0.019 sec)
Records: 0  Duplicates: 0  Warnings: 0

MariaDB [fechas]> update estudiante set edad = timestampdiff(year, dehcanacimiento, curdate());
ERROR 1054 (42S22): Unknown column 'dehcanacimiento' in 'field list'
MariaDB [fechas]> update estudiante set edad = TIMESTAMPDIFF(YEAR, fechanacimiento, CURDATE());
Query OK, 8 rows affected (0.013 sec)
Rows matched: 8  Changed: 8  Warnings: 0

MariaDB [fechas]> SELECT nombre, edad, IF(edad > 30, 'Hombre mayor', 'Joven en desarrollo') AS categoria FROM estudiante;
+------------------+------+---------------------+
| nombre           | edad | categoria           |
+------------------+------+---------------------+
| maria            |   58 | Hombre mayor        |
| juana            |   52 | Hombre mayor        |
| carlos           |   49 | Hombre mayor        |
| maria parra      |   48 | Hombre mayor        |
| pablo neruda     |   34 | Hombre mayor        |
| bladimir palacio |   30 | Joven en desarrollo |
| apolonia serrano |   31 | Hombre mayor        |
| federico serrano |   33 | Hombre mayor        |
+------------------+------+---------------------+
8 rows in set (0.001 sec)

MariaDB [fechas]> SELECT descripcion, IF(valor BETWEEN 200000 AND 300000, 'Materia econĒmica', 'Cara') AS categoria FROM materia;
+--------------+-------------------+
| descripcion  | categoria         |
+--------------+-------------------+
| software I   | Cara              |
| software II  | Cara              |
| software III | Cara              |
| matematicas  | Materia econĒmica |
| ingles       | Materia econĒmica |
+--------------+-------------------+
5 rows in set (0.002 sec)

MariaDB [fechas]> create table repaso2(
    -> codigo varchar(6) primary key,
    -> nombre varchar(50),
    -> sexo varchar(10),
    -> fechanacimiento date,
    -> nrohijos int
    -> );
Query OK, 0 rows affected (0.020 sec)

MariaDB [fechas]> insert into repaso2 values
    -> ('111222', 'carlos ramirez', 'hombre', '1969-04-04', 2),
    -> ('333666', 'marina ruiz', 'mujer', '1978-12-15', 3),
    -> ('999111', 'veronica gonzalez', 'mujer', '1982-03-30', 1),
    -> ('888777', 'isabel betancur', 'mujer', '1977-11-15', 1),
    -> ('333777', 'gladys bermudez', 'mujer', '1979-01-01', 2),
    -> ('444666', 'sandra henao', 'mujer', '1982-11-25', 3),
    -> ('555777', 'mario gomez', 'hombre', '1982-05-29', 2),
    -> ('111333', 'andrea gutierrez', 'mujer', '1985-04-12', 1),
    -> ('444777', 'carlos sepulveda', 'hombre', '1974-01-10', 1),
    -> ('555333', 'fernando perez', 'hombre', '1980-11-11', 4),
    -> ('666555', 'juliana arredondo', 'mujer', '1988-12-31', 2);
Query OK, 11 rows affected (0.008 sec)
Records: 11  Duplicates: 0  Warnings: 0

MariaDB [fechas]> SELECT COUNT(*) AS total FROM repaso2 WHERE nombre LIKE '%z';
+-------+
| total |
+-------+
|     7 |
+-------+
1 row in set (0.002 sec)

MariaDB [fechas]> SELECT COUNT(*) AS total FROM repaso2 WHERE YEAR(fechanacimiento) BETWEEN 1970 AND 1979;
+-------+
| total |
+-------+
|     4 |
+-------+
1 row in set (0.001 sec)

MariaDB [fechas]> SELECT * FROM repaso2 WHERE TIMESTAMPDIFF(YEAR, fechanacimiento, CURDATE()) BETWEEN 25 AND 30;
Empty set (0.002 sec)

MariaDB [fechas]> SELECT SUM(nrohijos) AS total_hijos FROM repaso2;
+-------------+
| total_hijos |
+-------------+
|          22 |
+-------------+
1 row in set (0.001 sec)

MariaDB [fechas]> SELECT nrohijos, COUNT(*) AS total FROM repaso2 GROUP BY nrohijos;
+----------+-------+
| nrohijos | total |
+----------+-------+
|        1 |     4 |
|        2 |     4 |
|        3 |     2 |
|        4 |     1 |
+----------+-------+
4 rows in set (0.002 sec)

MariaDB [fechas]> SELECT COUNT(*) AS total FROM repaso2 WHERE nombre LIKE 'carlos%';
+-------+
| total |
+-------+
|     2 |
+-------+
1 row in set (0.001 sec)

MariaDB [fechas]> SELECT COUNT(*) AS total FROM repaso2 WHERE sexo = 'mujer' AND TIMESTAMPDIFF(YEAR, fechanacimiento, CURDATE()) <= 22;
+-------+
| total |
+-------+
|     0 |
+-------+
1 row in set (0.013 sec)

MariaDB [fechas]> SELECT COUNT(*) AS total FROM repaso2 WHERE sexo = 'hombre' AND TIMESTAMPDIFF(YEAR, fechanacimiento, CURDATE()) > 30 AND nrohijos > 1;
+-------+
| total |
+-------+
|     3 |
+-------+
1 row in set (0.002 sec)

MariaDB [fechas]> SELECT COUNT(*) AS total FROM repaso2 WHERE sexo = 'mujer' AND TIMESTAMPDIFF(YEAR, fechanacimiento, CURDATE()) > 25 AND nrohijos BETWEEN 1 AND 3;
+-------+
| total |
+-------+
|     7 |
+-------+
1 row in set (0.002 sec)

MariaDB [fechas]> SELECT NOW() AS fecha_actual;
+---------------------+
| fecha_actual        |
+---------------------+
| 2025-03-25 00:32:30 |
+---------------------+
1 row in set (0.001 sec)

MariaDB [fechas]> SELECT CURTIME() AS hora_actual;
+-------------+
| hora_actual |
+-------------+
| 00:32:40    |
+-------------+
1 row in set (0.001 sec)

MariaDB [fechas]> exit